Pump lining



March 27, 1934. v. J. MILKOWSKI El AL. 1,952,179

PUMP LINlNG Filed Sept. 21. 1931 2 Sheets-Sheet l fl 2, M r. ga k srrs PUMP LINING Victor J. Millrowski, Baldwinsville, N. 2., and Paul F. Jahncke, New {)rleans, La.

Application September 21, 1931, Serial No. 563,956

1 Claim.

This invention relates to a lining for a centrifugal or other rotary pump and relates more particularly to a form of lining having a primary and a secondary lining, the secondary lining of lwhich is only exposed to wear under unusual circumstances, such as when the primary lining is non-homogeneous and wears through in certain spots only. I

The principal object of the invention is to prelo'ivent any wear of the main casing of the pump under any and all circumstances and to furthermore provide for wear by a special secondary lining only in the event that the primary lining becomes worn through.

'? Numerous other objects of the invention and practical solutions thereof are disclosed in detail in the herein patent specification, wherein:

in the accompanying drawings:

Fig. 1 is a vertical longitudinal section of a 2 0 Ioentrifugal pump adapted to pump abrasive material and provided with my improved form of dual lining.

Fig. 2 is a vertical transverse section thereof, taken on line 2+2, Fig. l. Fig. 3 is an enlarged fragmentary vertical transverse section of a modified form of dual pump lining.

In the following description similar characters of reference indicate like parts in the several to 'ifigures of the drawings.

Our invention may be embodied in various forms and in rotary pump linings of different constructions, and the present applications are therefore to be regarded merely as a small num- Tber of the possible organizations which come within the scope of our invention and satisfactorily carry out the function of same in practice.

As here shown and referring for the present only to Figs. 1 and 2, the same is constructed as follows:

Upon a suitable bed plate or foundation 10 is secured the usual form of pump casing 11. This casingand the organization of the pump in general is analogous to that disclosed in my cofpending applications for centrifugal pumps, Ser.

No. 428,593, filed Feb. 15, 1930 and Ser. No.

515,796, filed Feb. 14, 1931. This casing is provided with the usual front plate 12 which is secured to the main casing 11 by stud bolts 13 or btherwise, said front plate havinga central inlet duct 14 into which the semi-fluid, and more or less abrasive material being pumped, is drawn into the pump.

Rotatably and co-axiallly mounted within said pump casing 11 is the usual form of shrouded impeller 15 which is secured to the front conical end of a drive shaft 16 by a key 17 and securing nut 18. This drive haft i suitably iournaled at its outboard end in an anti-friction bearing 20 supported upon the foundation 16 by a pedestal 0o 2l. The forward end of said drive shaft is provided with a wear sleeve 22 which is rotatably journaled within a rubber bearing 23, leakage therefrom being prevented by a plurality of pack ing washers 24 which are adjustably compressed 05 by the usual form of packing gland 25.

As is well known in the art and more particularly when a centrifugal pump is used for nandling gritty or abrasive material such as in dredging work, etc., the wear on the main casing of the pump would entail excessively expensive repairs 'due to the fact that if the main casing wears through it would have to be entirely replaced, this being very uneconomical'by reason of the cost of said casing itself as well as the labor in- II volved in placing inposition and alining a new casing; To take care of abrasive wear in a more expedient manner it has been the custom for a long time to provide what we shall here term a primary metallic lining 26 which is suitably ma- '0 s chined on its outer annular flanges so as to accurately fit into bored annular interior faces of the main casing 11. Such linings have in actual practice been found to have one very serious defect. It has been found impossible to assure 88 that such linings be absolutely homogeneous and for this reason they are apt to wear through in those particular spots where the metal is relatively soft. It has been found furthermore that even when the metal of said lining 26 is substane 90 tially homogeneous the wear upon the same may be irregular due to irregular wear in localized parts of the pump or due to the excessive wear in certain spots due to the larger amount of flow of material thereagainst. In any event when the 98 lining as a whole has not worn through materially but has worn completely through in certain spots, the result has been that as soon as this occurs the main casing of the pump is worn through with extreme rapidity at such a spot or 100 spots due to the fact that the main casing is usually constructed merely of cast iron whereas the primary lining 26 is constructed of cast manganese steel or other like alloy. The presentinvention eliminates the danger of having the casing subjected to such localized wear by the provision of a secondary annular lining 27 constructed of rubber of suitable composition to withstand abrasion. This secondary resilient lining 27 is preferably received within and suitably cemented into an annular recess 28 which is formed upon the outer annular face of the circumferential wall 30 of the primary lining 26. The flat transverse end walls 31 of said primary lining 26 are not provided with any such resilient secondary lining 27 by reason of the fact that in actual practice these walls have to be made sufficiently thick to obtain proper structural strength as to never wear completely through. To illustrate the action of the present invention a worn-through localized spot 32 is illustrated, at which spot the metal of said lining 26 was relatively soft and at the same time subjected to a very considerable abrasion due to its position. This spot 32 is shown as being very localized in extent and extending entirely through the primary lining 26. t will be seen, however, that even under such circumstances the main casing 11 of the pump is not exposed to abrasive wear, being protected at this point by the secondary resilient lining 27. Such a resilient lining as is well known is considerably more resistant to abrasive wear than any metal, so that the main casing 11 of the pump, in the event of such a localized hole 32 being worn entirely through the primary lining 26, will protect the main casing until such a time will have arrived when it may be expected that the lining needs in pection; at which time, of course, the primary lining 26 would be replaced and also the secondary resilient lining 27, if necessary. It should be noted that the secondary resilient lining 27 is not normally subjected to abrasion, the wear ordinarily being taken by the primary metal lining 26, such a condition of afiairs being preferred in the particular sorts of work to which the present pump is particularly adapted. At the same time, as already noted, if the abrasion of said primary metallic lining should be so great in any one spot as to wear completely through, this resilient secondary lining 27 will prevent the main casing 11 from being injured. In other words, the present invention acts in the nature of a safeguard in the event of localized wear, it not being intended to function in such cases where the wear on the primary metallic lining 26 is uniform, but only, as heretofore pointed out, where said primary lining has soft spots or for other reasons is locally worn entirely through long before the pump has been in service sufficiently long to warrant the operators believing that an inspection of the lining is necessary.

In Fig. 3 is shown a slight modification of the invention. In this case, as before, the pump is provided with a primary metallic lining 261, which is suitably received within the main pump casing 111 and a secondary resilient lining 271 being suitably received within a recess 281 formed in the peripheral face of said primary lining 261. In this case, however, instead of merely cementing the resilient lining into said recess 281 a supplemental wearing plate 35 of annular form is suitably welded at its edges 36 to said primary lining. Thus in this construction the secondary resilient lining 271 is metallically covered on both of its faces so that there is less likelihood of its being injured or allowed to deteriorate prior to the time that it, together with its companion primary metallic lining 261, is placed into the main pump casing 111. This may seem to be an undue refinement, but it should be borne in mind that the isolated conditions in which such pumps work and the caliber of labor employed is such as to subject any spare parts (such as the primary lining in question) to very severe use.

We claim as our invention:

A rotary pump comprising a casing; a primary lining disposed Within said casing; a resilient lining interposed between said casing and said primary lining; an impeller rotatably mounted Within said primary lining; and a securing plate disposed between said resilient lining and said casing and secured to said primary lining.

VICTOR J. MILKOWSKI. PAUL F. JAI-INCKE. 

